Patients receive gemcitabine IV over 30-60 minutes on days 1, 4, 8, 11, 15, 18, 22, 25, 29, and 32 and undergo radiotherapy on days 1-5, 8-12, 15-19, 22-26, 29-33, and 36-38 in the absence of disease progression or unacceptable toxicity.